FIELD OF THE INVENTION
This invention relates to a notification system for television receivers, and more particularly, to a visible and/or an audible alarm that is activated when a certain event occurs, such as reception of a data message or the televising of a certain program.
A television receiver is present in most homes in the United States. Many homes are connected to receive cable television signals in addition to broadcast signals while some can only receive broadcast signals. Recently, other types of service have become available such as direct broadcast satellite (DBS). In the near future, television signals may be provided to the home via telephone lines and/or direct wireless links.
Even as the amount of programming has increased, the primary source of program scheduling information is a paper listing published in a newspaper or magazine. Recently, StarSight Telecast, Inc. (SST) has introduced an Interactive Program Guide (IPG) data channel that is provided through the signal transmitted by a single television channel (e.g. in the vertical blanking interval (VBI) of the local Public Broadcasting System (PBS) affiliate). The IPG is also known as an Electronic Program Guide (EPG). The IPG data is processed by a microcomputer in the television receiver to produce an on-screen television guide that provides the viewer with information such as the upcoming television programs on all broadcast and cable channels, program plot summaries, and the name of and time remaining in each program currently being transmitted on each of the broadcast and cable channels. This information is available even if the viewer changes channels or if a commercial is being televised. The SST system is described in U.S. Pat. Nos. 4,706,121, entitled TV SCHEDULE SYSTEM AND PROCESS; 4,977,455, entitled SYSTEM AND PROCESS FOR VCR SCHEDULING; and 5,151,789, entitled SYSTEM AND METHOD FOR AUTOMATIC, UNATTENDED RECORDING OF CABLE TELEVISION PROGRAMS, which patents are hereby incorporated by reference for their teachings on microcontrollers used in a television environment and on the operation and structure of IPG systems.
In addition to SST, other competing services are currently being planned or offered. For example, each of the existing DBS systems offers an IPG service for its own programs. This IPG data may be decoded by circuitry similar to that used to decode the SST IPG except that, for DBS signals, the circuitry may reside in the DBS decoder rather than in the television receiver.
In addition to IPG systems, other systems exist which transfer data using television signals. These include Teletext, Videotex, Extended Data Services (XDS) and Closed Captioning. In each of these systems, data are transferred during the VBI of one or more television signals. All of these systems have certain hardware elements in common, circuitry which is used to extract the data from the VBI and a processor which formats the extracted data for display.
Other types of systems currently are being planned or implemented under the general heading of Interactive Television. Using these systems, message data, such as text and/or graphic messages containing communications, news, weather, and user-requested information may be sent to television receivers. These messages may be sent with a unique identifier that matches the identification code of the intended recipient (i.e. an identification code in the television receiver). Because the personal messages are sent with the identification code of the intended recipient, only he or she will be able to view the message even though it is broadcast to all local users of the system. These messages may also be sent without an identification code or with a general identifier. Messages of this type will be received by all users of the system.
A block diagram of a typical television receiver having an integrated data service in accordance with the prior art is shown in FIG. 1.
The incoming television signal is received by an antenna or a cable 100. A tuner 105, controlled by a host microcontroller 110, selects a particular channel signal and demodulates the signal to recover a baseband video signal and an audio signal. The tuner 105 receives power even when the television is turned off so that it may continue to receive and decode data from the data service.
The audio signal is passed to audio processing circuitry 115 which produces a signal for the speaker 116 when the television is turned on. The baseband video signal is passed to video processing circuitry 120 and to data decode circuitry 125. The video processing circuitry 120 includes video decode and display circuitry 121 which, in turn, includes circuitry such as a comb filter (not shown), peaking circuitry (not shown) and matrixing circuitry (not shown). The circuitry 121 separates the luminance and chrominance components of the video signal and converts the separated component signals into red (R), green (G) and blue (B) color signals. The RGB signals are applied to a video mixer 132.
The composite video signals are also applied to a scan system 123 which separates the horizontal and vertical sync components of the television signal and generates timing signals that are applied to the video decoding circuitry 121, the deflection system 134 and data decoding circuitry 125. The decoding circuitry 125 receives the baseband video signal and, responsive to the timing signals provided by the scan system, separates the data transmitted in the vertical blanking interval, stores the data for future reference and passes the decoded data to on-screen display circuitry 130. The data decoding circuitry also exchanges information with the microcontroller 110. The microcontroller 110 is used by the television receiver to implement the user controls, such as channel selection, volume, contrast, brightness, hue and color as well as to process the data received during the vertical blanking interval.
The system also includes an electronic clock 111, which may be accessed by the microcontroller 110 to determine the current time.
The information transferred by the data decoder 125 and the microcontroller 110 may, for example, be user commands requesting that specific data be displayed and signals notifying the microcontroller that particular data has been received and decoded. The same data decoder 125 may be used for multiple functions, for example, to decode IPG data for a service such as StarSight and to decode closed captioning data. The data decoding circuitry 125 is coupled to the on-screen display circuitry 130 to allow the IPG information to be formatted and displayed.
The host microcontroller 110 is also connected to the on-screen display circuitry 130 to generate on-screen menus that are used in conjunction with the control functions implemented via the microcontroller 110.
The microcontroller 110 and data decoding circuitry 125 continue to operate even when the television receiver is turned off so that they may continue to decode the IPG, Teletext or Videotex data.
The video output signals of the on-screen display circuitry 130 are applied to the video mixer 132. The mixer 132 combines the on-screen display signal with the received video signals to produce a composite display. This display may, for example, combine active video with control menu displays, add a closed caption display to a video signal or display information from the IPG in a window inset into the active video image. The combined image is displayed on a display device, such as CRT 136, under control of the deflection system 134.
A data message sent along with the IPG, Teletext, Videotex or Closed Captioning data signal may be decoded by a data decoder 125 and further processed for display by the circuitry 130.
As described above, interactive television systems may also be used to transmit personal messages which may only be viewed on a television receiver having a unique address code. For these systems, a user will be notified that a message has been received as soon as the television receiver is turned on.